A passenger bus in Afghanistan collided on Friday with a wrecked fuel tanker left on a road after a Taliban insurgent attack, killing at least 45 people, officials said.

A passenger bus in Afghanistan collided on Friday with a wrecked fuel tanker left on a road after a Taliban insurgent attack, killing at least 45 people, officials said.

The accident occurred before dawn in the Maiwand district of Kandahar province when the packed bus ploughed into the tanker, which had been burnt out in a Taliban strike several days ago.

"Tragically, around 4:00am, the passenger bus collided with a fuel tanker," Javid Faisal, spokesman for the Kandahar provincial governor, told AFP. "We have 45 passengers dead in this accident and ten others wounded."

"The wreckage of a truck, which was put alight by the Taliban, was left there for several days, and the bus collided with it."

Many of those hurt were travelling to join the short "neishtar" harvest season, when villagers from across southern Afghanistan work in poppy fields during one of the most lucrative times of the year for casual labourers.

A neishtar is the small lance used to make incisions on poppy plants to let out the resin, which dries into solid opium residue.

Faisal had earlier denied reports that the wrecked tanker had been set on fire by Taliban insurgents, who are highly active in Kandahar province, one of the hotbeds of the insurgency fighting to oust the US-backed Kabul government.

The bus had just crossed the border into Kandahar from Helmand province when it hit the tanker.

"We were more than 50 passengers in the bus. Most of the passengers were men," Faizullah, one of the passengers who survived the accident, told AFP.

"Our vehicle caught fire. I broke the glass of the vehicle and then jumped. I heard people yelling for help."

Afghanistan has some of the most dangerous roads in the world and traffic accidents are common.

In September, 51 passengers including women and children, were killed after their bus also collided with a fuel tanker in Ghazni province.